Second
prototype of what to became Tu-2, built in
April 1941
shortly after the '103' (ANT-58). Aircraft size was slightly larger and heavier. It
also differed from other members of Tu-2 family by small cooling air intakes in
propeller spinners.

VVS demanded to change the
crew, and it was done. Navigator was moved to share front
cockpit with pilot and got additional ShKAS defensive gun. At the same time
nose mounted machineguns were deleted. Ten hardpoints for RS-132 rockets were added.

Test-pilot M.A.Nukhtikov and engineer V.A.Miruts took '103U' into the air on May 18,
1941.
Despite performance was slightly worser than of the
'103', aircraft still was far better than anything in production.

Series production started in September
1941,
but production of AM-37 engines was cancelled in favor of
AM-38 (to equip Il-2 produced at
enormous pace). Designers had to redesign aircraft for other engine...